Both Sony A9 II and Panasonic S1 have Full frame sized 24.0 MP resolution sensors so sensor size and resolution is not a differentiator between these two cameras.
One other difference between these two cameras that is worth mentioning is that Panasonic S1's sensor doesn't have an anti-alias (Low-Pass) filter. Removing anti-alias filter increases the sharpness and level of detail but at the same time, it increases the chance of moiré occurring in certain scenes.
Below you can see the A9 Mark II and S1 sensor size comparison.
Sony A9 II and Panasonic S1 have the same sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture.
DxOMark Sensor Scores
DxOMark is a benchmark that scientifically assesses image quality of camera sensors. It scores camera sensors for color depth (DXO Portrait), dynamic range (DXO Landscape) and low-light sensitivity (DXO Sports), and also gives them an overall score. Sony A9 II and Panasonic S1 sensors have been tested by DxO and the results show that S1 has a better overall score of 95, 2 points higher compared to A9 Mark II's score of 93.
Model |
Overall |
Color Depth |
Dynamic Range |
Low-light ISO |
Sony A9 II |
93 |
25.0 bits |
14.0 Evs |
3434 ISO |
Panasonic S1 |
95 |
25.2 bits |
14.5 Evs |
3333 ISO |